1. Field of the Invention
The invention is directed to a data transmission system which has an improved data format.
2. Description of the Prior Art
Such a system is known in the form of what is referred to as the ISDN-S.sub.O or S/T interface for the ISDN base terminal of an integrated services digital telecommunications network (Fernmeldepraxis, No. 19/20, 1985, pp. 759-762).
Data transmission systems which utilize bit rates of less than about 200 kbit/s are known in the prior art. The subscriber-line technology in the integrated services digital network is divided into a first area of switching to the subscriber, and into a second area of the installation at the subscriber. A network termination unit NT with a U-interface on the network switching side and a S/T-interface on the subscriber's side, installed at the subscriber, serves as a tie between the two areas. A connection between the network termination unit NT and up to eight terminal devices of the same kind or of a different kind occurs via two pairs of a S-bus. The transmission at the S/T-interface occurs with a bit rate of 192 kbit/s.